Activity Overview
Is the iconic arch of the Sydney Harbour Bridge a parabola or a catenary? In this activity students determine equations for the two arches on the Sydney Harbour bridge and the roadway using different techniques. Students perform calculations to check the accuracy of the modelling and apply the models to determine the total length of the cables.
Objectives
Students practice generating quadratic equations. Two methods are used, one uses axis intercepts (factorised form) and dilation (using y axis intercept) the other technique is the transformed function (turning point) and dilation (point on the curve). In addition to practicing these techniques, students gain a better understanding of the modelling process.
Vocabulary
- Factors and axis Intercepts
- Turning point and Turning point form
- Dilation factor
- Modelling
- Subtraction of ordinates
About the Lesson
Students orientate the cartesian plane into an appropriate location so they can generate a variety of equations to model the iconic Sydney Harbour bridge. Students use a range of techniques, the image provides direct feedback to students regarding their calculations.